mvw2
03-10-2008, 03:28 AM
Overview
I'm writing this as a basic setup guide for people running active.
This guide is just my particular way of tuning a system. It is not an end-all, just my humble aproach
Coverage
Driver balance
EQ balance
Time alignment
Stage balance
Subwoofer integration
Driver Balance
When pairing two or more drivers together, it is important to get an initial balance between each driver to account for the relative sensitivity differences that exist. You can generally start off with a rough guess using manufacturer specs, but you can work on the fly as well. This can be done listening to music and balancing out the relative intensity so neither overwhelms the other or via test tones or my preferred pink noise. I've come to love pink noise quite a bit and pretty much use it exclusively for tuning. This guide will follow my little route for tuning, so I will focus on pink noise use exclusively. It doesn't have to be pink noise, but, for me, it works very, very well.
Approach driver balance one side at a time. Set balance all the way to the left or right only so you're working with just one set of speakers. This makes things easier. I will follow the same approach later with EQing. Run the right speakers only. Play the pink noise track. Adjust relative output between the woofer and tweeter till both have the same relative intensity. Now run the left speakers only and balance relative intensity. Realize at this point, we are not really EQing the speakers. We are just getting a good starting point where the woofer and tweeter aren't too far off from each other. At this point, I won't bother with the subwoofer yet. I suggest focusing on the front stage only till it's finished. Then the subwoofer can be integrated in from there.
EQ Balance
Now that we have a rough starting point, we can come in and fine tune the response across the entire frequency spectrum. Now this step will be approached in several ways depending on what type and level of EQing you have. The setup from here will depend on if you are running a parametric or graphic and if you have separate left and right EQ control. I have a personal preference towards graphic of about 10 bands or more and have become very fond of seperate left and right EQing ability. I'll explain the differences as we go through this. Again, adjust so only the right side plays, and again play the pink noise track.
For the graphic EQ folks, simply run through each band and raise or lower the level to get a flat response. No band should overpower another and every frequency range should sound equal in intensity. No band should stand out or be lacking. Take your time with this and run through each band a few times till you feel it's good. Once you're done, move over to the left pair of speakers only and repeat. Write down on paper the curve you made for each side.
For the parametric EQ folks, you'll need to do the same approach but since yours are adjustable, it would be best to test and record bumps or cuts as you test each frequency point but don't set anything in stone yet. Get a full list of what you did and if you only have a few parametric points, pick the worst spots and fix them. Once you're there, play around with the values a little and see what's better. Raise or lower the bump or cut a tiny bit, bump the frequency point down or up one notch, and raise or lower the Q value. Pick the best fit. If you've got more parametric bands, 5 or 7 as some have, you have a lot more power and can really flatten out the curve. However, you kind of see how much harder it is than the simple hack and slash you do with a graphic type. I kind of find parametric bitter sweet. Once you're done with the right side, go to the left side only and repeat and get a different curve. Record both the right and left curves on paper.
Now for those of you who have a single, shared EQ, it's time to sacrifice. You have two, different curves you made that represent the (ear) flat output for each side. The final setup will be somewhere in between both. If you want, you can simply cut the difference in half and set the EQ there. This would be a halfway compromise for each side and provide a decent overall response. You might also try playing both sides together and retuning the EQ playing both the left and right together. Just try to find a happy medium.
For the folks with seperate left and right EQs, you have your two curves. Set them and you're done for the moment.
I will note that in my experience, I found pink noise to not really be influenced by time alignment settings. Since it's just a constant noise, there really isn't an issue with dominance by order received by the ear. In normal notes, the dominant sound is the one that reaches your ear first. With pink noise, it's just always there and always constant so the mind only interprets raw intensity. Basically, I'm just saying if you're worried about TA messing this up, don't be.
Time Alignment
Now it's time to get everything synced together. It's useful to start off with physical measurements using just a simple tape measure. It will get you a very close starting point. From there you should be withing a couple notches of spot on.
Play whatever music you like. You might find certain songs to fair better than others. It's useful to know what is in the song in terms of center, left, and right singers and instruments. Some songs fade back and forth for effect, and some move around, so ease of setup for time alignment can be song dependent. The goal here is to create a coherent, in-sync presence.
Again, start with just the right side speakers. Play the music and fine tune the relative delay between each. If you listen carefully as you adjust, you can feel the sound pull you to the woofer and then the tweeter and back again, depending on whichever gets to your ear first. Set the TA in the middle so that both sound in sync and neither overshadowing the other. Now move to the left side and repeat.
Finally, run both the left and right together and sync the left and right to a coherent presence. The relative TA between the tweeter and woofer should stay the same. You are now only adjusting the whole side in or out. You should be able to feel the stage pull towards the left or right as one side becomes dominant and then the other. Again, you are finding the middle spot where both are equal and the stage is centered. I'll make one note here. This stage setup is dependent on the relative outputs of the right and left side, so you may have a tough time finding the center till we address the final step. We'll probably have to go back and forth between the final step and readjusting the overall right and left TA to dial it together. Just find a happy medium right now, and we'll dial it in later.
Stage Balance
This is the final process to get everything sewn together neatly. This is more of a fine tuning process but does come in two parts.
Part 1: Adjust relative right and left outputs.
Now, we have yet to address relative output between the right and left speakers. We addressed the woofer <==> tweeter relationship through attenuation and later EQing, but we haven't addressed the left <==> right relationship. At this point, we are simply adjusting the balance between the left and right speakers till both are of the same relative loudness. As you adjust the left louder, the presence should pull left and become dominant. If you make the right louder, the presence pulls right. Note that TA will have the same effect. This means that we actually need to adjust both at the same time to really dial it in. This may take a little fiddling, but focus on getting the relative intensity the same between the left and right sides. At the same time, adjust TA so that the presence isn't pulled towards the left or right but rather is centered. If the stage is right side dominant, we have the option of both lowering the right side output or decreasing the delay of the right side to make the left side more dominant. Realize that this isn't a "either one works" thing. Only one option is correct, so you sort of have to try it and then try it again. In the end, we want equal intensity AND a centered stage. It sounds tricky, but it's actually pretty straight forward and we should have been pretty close with the tape measure to begin with. It should just be minor tweaking really.
Part 2: EQ balance
The final step is to equalize the relative intensity throughout the frequency spectrum. We should have gotten very close already from the earlier right and left EQing sessions. Now we just have to run a check. Go through the frequency spectrum again and bump or cut a notch at each point and see where it pulls the stage presence. You should be able to notice the stage at that frequency range move right or left as you adjust. Again, the focus is center. We want the stage centered at every EQ frequency. It should really only take 1dB here or there(or 0.5dB for some folks) or a minor tweak in Q to get everything centered as best you can. The goal with this final step is to create a solid and consistent center image. Not doing this step can create the wavy center and noticeable changes in position as the music moves up and down the frequency spectrum. With the intensity equal at all frequency points(well as close as we can get it), the center remains center, left stays left, right stays right, and everything in between stays where it should be. This is the goal at least.
Subwoofer Integration
After all the above fun, the subwoofer should be pretty straight forward. Again, you are following similar steps. Adjust relative intensity to blend and match with the front stage. Adjust TA to sync the sub to the front stage. A tape measure is a very good tool to start with and fine tune from there. Those with ported boxes, think about group delay. You might be 10 to 20 milliseconds off already, so adjust for it if you need to. It's best to toy by ear till it sounds right and in sync. Again, work through any available EQing bands to flatten out the response. Some of you may have a good amount of EQing power available down low, some not. Get a happy medium. Again, TA will affect relative perception, so work with a mix of TA and attenuation till you get a seemless integration with the front stage. You're really just doing a repeat of the above steps, just anding one more driver to the mix. It's just easier because there's just one, not 4, and there's no relative centering involved. Like I said, after the above stuff, this should feel pretty straight forward and easy.
Final Notes
I'll make one final note. This setup is tuned for one person, the main listener. The tune should be done with the listener in the car, sitting in the normal listening location. Make note of hand and leg positions. For the folks with door and kick-panel installs, just the location of your leg can make or break the stage. The final step will actually vary a little bit depending and where and how you sit, so keep that in mind. You also see why it's kind of nice to run tweeters up in the a-pillar versus in the door or kick or stepping to a 3-way with both the mid and tweeter up high and unobstructed. If you want, you may even consider tuning with a passenger in the car if that's the common configuration(many days of car pooling).
Also keep in mind subwoofer location. Move it around and see where you like it best. Generally as close to the rear as possible is best. I've become fond of upward facing subs(hatch/wagon install), but rearward facing scooted all the way back is the most common and is generally considered the best. Just realize if the sub moves, relative intensity changes, both by proximity and the time domain so attenuation and TA needs to be readjusted.
That's it. This is basically how I approach my setup. It's not the only way of doing things. Heck, it may not be a great way of doing things, but it's something I've found that works well for me. I do find graphic EQs easier and quicker to use but agree parametric ones give a little better, smoother response. That's really just a preference in how you want to interact with the response curve. I feel about 10 graphic bands do plenty well, but if you have more you're better off. The more you have, the smoother the final response. For the reasons mentioned earlier and through the general approach of this tune, it's easy to see that separate left and right EQs are quite handy and can be the final tool on your side to dial in the stage. I've become quite fond and do suggest looking into options if you do not already have this nice feature. I love pink noise. I just find it...unbiased, and given a little ear accustoming, your mind can discern relative changes quite easy. It just doesn't work for TA.
I'm writing this as a basic setup guide for people running active.
This guide is just my particular way of tuning a system. It is not an end-all, just my humble aproach
Coverage
Driver balance
EQ balance
Time alignment
Stage balance
Subwoofer integration
Driver Balance
When pairing two or more drivers together, it is important to get an initial balance between each driver to account for the relative sensitivity differences that exist. You can generally start off with a rough guess using manufacturer specs, but you can work on the fly as well. This can be done listening to music and balancing out the relative intensity so neither overwhelms the other or via test tones or my preferred pink noise. I've come to love pink noise quite a bit and pretty much use it exclusively for tuning. This guide will follow my little route for tuning, so I will focus on pink noise use exclusively. It doesn't have to be pink noise, but, for me, it works very, very well.
Approach driver balance one side at a time. Set balance all the way to the left or right only so you're working with just one set of speakers. This makes things easier. I will follow the same approach later with EQing. Run the right speakers only. Play the pink noise track. Adjust relative output between the woofer and tweeter till both have the same relative intensity. Now run the left speakers only and balance relative intensity. Realize at this point, we are not really EQing the speakers. We are just getting a good starting point where the woofer and tweeter aren't too far off from each other. At this point, I won't bother with the subwoofer yet. I suggest focusing on the front stage only till it's finished. Then the subwoofer can be integrated in from there.
EQ Balance
Now that we have a rough starting point, we can come in and fine tune the response across the entire frequency spectrum. Now this step will be approached in several ways depending on what type and level of EQing you have. The setup from here will depend on if you are running a parametric or graphic and if you have separate left and right EQ control. I have a personal preference towards graphic of about 10 bands or more and have become very fond of seperate left and right EQing ability. I'll explain the differences as we go through this. Again, adjust so only the right side plays, and again play the pink noise track.
For the graphic EQ folks, simply run through each band and raise or lower the level to get a flat response. No band should overpower another and every frequency range should sound equal in intensity. No band should stand out or be lacking. Take your time with this and run through each band a few times till you feel it's good. Once you're done, move over to the left pair of speakers only and repeat. Write down on paper the curve you made for each side.
For the parametric EQ folks, you'll need to do the same approach but since yours are adjustable, it would be best to test and record bumps or cuts as you test each frequency point but don't set anything in stone yet. Get a full list of what you did and if you only have a few parametric points, pick the worst spots and fix them. Once you're there, play around with the values a little and see what's better. Raise or lower the bump or cut a tiny bit, bump the frequency point down or up one notch, and raise or lower the Q value. Pick the best fit. If you've got more parametric bands, 5 or 7 as some have, you have a lot more power and can really flatten out the curve. However, you kind of see how much harder it is than the simple hack and slash you do with a graphic type. I kind of find parametric bitter sweet. Once you're done with the right side, go to the left side only and repeat and get a different curve. Record both the right and left curves on paper.
Now for those of you who have a single, shared EQ, it's time to sacrifice. You have two, different curves you made that represent the (ear) flat output for each side. The final setup will be somewhere in between both. If you want, you can simply cut the difference in half and set the EQ there. This would be a halfway compromise for each side and provide a decent overall response. You might also try playing both sides together and retuning the EQ playing both the left and right together. Just try to find a happy medium.
For the folks with seperate left and right EQs, you have your two curves. Set them and you're done for the moment.
I will note that in my experience, I found pink noise to not really be influenced by time alignment settings. Since it's just a constant noise, there really isn't an issue with dominance by order received by the ear. In normal notes, the dominant sound is the one that reaches your ear first. With pink noise, it's just always there and always constant so the mind only interprets raw intensity. Basically, I'm just saying if you're worried about TA messing this up, don't be.
Time Alignment
Now it's time to get everything synced together. It's useful to start off with physical measurements using just a simple tape measure. It will get you a very close starting point. From there you should be withing a couple notches of spot on.
Play whatever music you like. You might find certain songs to fair better than others. It's useful to know what is in the song in terms of center, left, and right singers and instruments. Some songs fade back and forth for effect, and some move around, so ease of setup for time alignment can be song dependent. The goal here is to create a coherent, in-sync presence.
Again, start with just the right side speakers. Play the music and fine tune the relative delay between each. If you listen carefully as you adjust, you can feel the sound pull you to the woofer and then the tweeter and back again, depending on whichever gets to your ear first. Set the TA in the middle so that both sound in sync and neither overshadowing the other. Now move to the left side and repeat.
Finally, run both the left and right together and sync the left and right to a coherent presence. The relative TA between the tweeter and woofer should stay the same. You are now only adjusting the whole side in or out. You should be able to feel the stage pull towards the left or right as one side becomes dominant and then the other. Again, you are finding the middle spot where both are equal and the stage is centered. I'll make one note here. This stage setup is dependent on the relative outputs of the right and left side, so you may have a tough time finding the center till we address the final step. We'll probably have to go back and forth between the final step and readjusting the overall right and left TA to dial it together. Just find a happy medium right now, and we'll dial it in later.
Stage Balance
This is the final process to get everything sewn together neatly. This is more of a fine tuning process but does come in two parts.
Part 1: Adjust relative right and left outputs.
Now, we have yet to address relative output between the right and left speakers. We addressed the woofer <==> tweeter relationship through attenuation and later EQing, but we haven't addressed the left <==> right relationship. At this point, we are simply adjusting the balance between the left and right speakers till both are of the same relative loudness. As you adjust the left louder, the presence should pull left and become dominant. If you make the right louder, the presence pulls right. Note that TA will have the same effect. This means that we actually need to adjust both at the same time to really dial it in. This may take a little fiddling, but focus on getting the relative intensity the same between the left and right sides. At the same time, adjust TA so that the presence isn't pulled towards the left or right but rather is centered. If the stage is right side dominant, we have the option of both lowering the right side output or decreasing the delay of the right side to make the left side more dominant. Realize that this isn't a "either one works" thing. Only one option is correct, so you sort of have to try it and then try it again. In the end, we want equal intensity AND a centered stage. It sounds tricky, but it's actually pretty straight forward and we should have been pretty close with the tape measure to begin with. It should just be minor tweaking really.
Part 2: EQ balance
The final step is to equalize the relative intensity throughout the frequency spectrum. We should have gotten very close already from the earlier right and left EQing sessions. Now we just have to run a check. Go through the frequency spectrum again and bump or cut a notch at each point and see where it pulls the stage presence. You should be able to notice the stage at that frequency range move right or left as you adjust. Again, the focus is center. We want the stage centered at every EQ frequency. It should really only take 1dB here or there(or 0.5dB for some folks) or a minor tweak in Q to get everything centered as best you can. The goal with this final step is to create a solid and consistent center image. Not doing this step can create the wavy center and noticeable changes in position as the music moves up and down the frequency spectrum. With the intensity equal at all frequency points(well as close as we can get it), the center remains center, left stays left, right stays right, and everything in between stays where it should be. This is the goal at least.
Subwoofer Integration
After all the above fun, the subwoofer should be pretty straight forward. Again, you are following similar steps. Adjust relative intensity to blend and match with the front stage. Adjust TA to sync the sub to the front stage. A tape measure is a very good tool to start with and fine tune from there. Those with ported boxes, think about group delay. You might be 10 to 20 milliseconds off already, so adjust for it if you need to. It's best to toy by ear till it sounds right and in sync. Again, work through any available EQing bands to flatten out the response. Some of you may have a good amount of EQing power available down low, some not. Get a happy medium. Again, TA will affect relative perception, so work with a mix of TA and attenuation till you get a seemless integration with the front stage. You're really just doing a repeat of the above steps, just anding one more driver to the mix. It's just easier because there's just one, not 4, and there's no relative centering involved. Like I said, after the above stuff, this should feel pretty straight forward and easy.
Final Notes
I'll make one final note. This setup is tuned for one person, the main listener. The tune should be done with the listener in the car, sitting in the normal listening location. Make note of hand and leg positions. For the folks with door and kick-panel installs, just the location of your leg can make or break the stage. The final step will actually vary a little bit depending and where and how you sit, so keep that in mind. You also see why it's kind of nice to run tweeters up in the a-pillar versus in the door or kick or stepping to a 3-way with both the mid and tweeter up high and unobstructed. If you want, you may even consider tuning with a passenger in the car if that's the common configuration(many days of car pooling).
Also keep in mind subwoofer location. Move it around and see where you like it best. Generally as close to the rear as possible is best. I've become fond of upward facing subs(hatch/wagon install), but rearward facing scooted all the way back is the most common and is generally considered the best. Just realize if the sub moves, relative intensity changes, both by proximity and the time domain so attenuation and TA needs to be readjusted.
That's it. This is basically how I approach my setup. It's not the only way of doing things. Heck, it may not be a great way of doing things, but it's something I've found that works well for me. I do find graphic EQs easier and quicker to use but agree parametric ones give a little better, smoother response. That's really just a preference in how you want to interact with the response curve. I feel about 10 graphic bands do plenty well, but if you have more you're better off. The more you have, the smoother the final response. For the reasons mentioned earlier and through the general approach of this tune, it's easy to see that separate left and right EQs are quite handy and can be the final tool on your side to dial in the stage. I've become quite fond and do suggest looking into options if you do not already have this nice feature. I love pink noise. I just find it...unbiased, and given a little ear accustoming, your mind can discern relative changes quite easy. It just doesn't work for TA.